Alkylimidazolidone acrylates and methacrylates are known for their role in the constitution of polymers which can be used as coatings and adhesives, in the treatment of paper and of textiles, for their use as agents for leather treatment and in the production of emulsion paints.
European patent application No. 236 994 relates to the preparation of esters of (meth)acrylic acid by reacting an alkyl (meth)acrylate with a heterocyclic alcohol in the presence of a catalyst that is a titanium alkoxide or a titanium, zirconium, iron or zinc chelate, combined with a 1,3-dicarbonyl compound, which may be a metal chelate of a 1,3-diketone, in particular an acetylacetonate.
Such a catalyst has the major disadvantage of generating intensely coloured products.
European patent application No. 433 135 relates to a process for the synthesis of an alkylimidazoline (meth)acrylate, in which an alkyl (meth)acrylate is reacted with a heterocyclic alcohol in the presence of a catalyst chosen from dialkyl tin oxides, dialkyl tin dialkoxides and dialkyl tin diesters.
Such a catalyst requires high reaction temperatures and often causes violent polymerizations with formation of a very hard expanded polymer.
European patent application No. 453 638 also relates to the synthesis of an alkylimidazoline (meth)acrylate in the presence of dialkyl tin oxide.
The subject of European patent application No. 571 851 is a process for the preparation of alkylimidazoline (meth)acrylate, by transesterification of an alkyl (meth)acrylate by means of a heterocyclic alcohol, in the presence of a catalytic system which is a combination of a catalyst based on lithium, for example in oxide, alkoxide, acetate, chloride or bromide form, and a catalyst based on calcium, such as calcium oxide.
European patent application No. 619 309 relates to the preparation of alkylimidazoline (meth)acrylate by reacting an alkyl (meth)acrylate with a heterocyclic alcohol in the presence of a catalyst chosen from the chelates of calcium with 1,3-dicarbonyl compounds, such as calcium acetylacetonate. The products obtained by the process described in that document has an excessively strong colour.
Finally, European patent application No. 902 017 mentions the use of a catalyst that may be lithium, lithium carbonate or lithium hydroxide in the preparation of a monomer from, in particular, hydroxyethyloxazolidine and methyl methacrylate.
However, the use of such catalytic systems does not make it possible to simultaneously achieve the following main objectives:                a high conversion of the heterocyclic alcohol;        a low content of by-products;        a high kinetic;        a low thermal level; and        a faint colouring of the final product.        
The subject of the invention is a process for the preparation of alkylimidazoline (meth)acrylate, a process which makes it possible to achieve the objectives mentioned above.
Specifically, the subject of the invention is a process for the preparation of compound (I):

wherein:                R1 is a hydrogen atom or a methyl group; and        A and B represent, independently of each other, a straight- or branched-chain alkylene group having from 2 to 5 carbon atoms;        
by reacting at least one (meth)acrylate (II):

wherein:                R1 has the abovementioned meaning; and        R2 is a straight- or branched-chain alkyl group having from 1 to 4 carbon atoms;        
with a heterocyclic alcohol (III):

wherein A and B have the abovementioned meanings;
in the presence of a catalyst comprising at least one compound (a) which is a chelate formed of lithium and of a 1,3-dicarbonyl compound.
The subject of the invention is also a composition comprising compound (I) obtained by the process according to the invention in solution in (meth)acrylate (II).
Finally, the subject of the invention is also the use of the abovementioned composition in the preparation of polymers that can be used as coatings and adhesives, in the treatment of paper and of textiles, as agent for leather treatment and in the production of paints with high wet adhesion characteristics.